Exotic hadrons from dynamical clustering of quarks in ultrarelativistic heavy ion collisions

Results from a model study on the formation of exotic quark clusters at the hadronization stage of a heavy ion collision are presented. The dynamical quark molecular dynamics (qMD) model which is used is sketched, and results for exotica made of up to six (anti-)quarks are shown. The second part focuses on pentaquarks. The rapidity distribution are shown, and the distribution of strangeness is found to yield an indicator of thermalization and homogenisation of the deconfined quark system. Relative Theta^+ yields are found to be lower than thermal model estimates.Comment: 4 pages, 5 figures, to appear in the proceedings of Strangeness in Quark Matter 2004 (SQM2004), Cape Town, South Africa, 15-20 September 200

Policy for sustainable entrepreneurship: a crowdsourced framework

Sustainable entrepreneurship—entrepreneurship with social and ecological gains as well as economic ones—has the potential to play a significant role in addressing societal and environmental challenges. However, sustainability and entrepreneurship have hitherto been addressed through separate policy regimes, and it is not clear how policymakers can encourage sustainable entrepreneurship specifically. The authors develop a policy framework for sustainable entrepreneurship, using an open innovation approach with policymakers, business executives, academics, entrepreneurs and other relevant actors, including an online crowdsourcing event with 150 participants. The framework incorporates five policy domains: creating awareness and skills; building networks; funding and investing; measuring impact and performance; and innovating government. The article proposes a modified version of the multi-level perspective (MLP) on how socio-technical transitions occur, since the findings suggest that policy can catalyze the facilitation and aggregation of innovations coming from the niche level, thereby evolving the socio-technical regime, in addition to the role of policy described in earlier work in stabilizing the socio-technical regime. Contributions to entrepreneurship policy literature include the policy domain of measuring impact and performance, as appropriate success measures are non-trivial in a triple bottom line environment, and the potential for open policy innovation in entrepreneurship policy. Contributions to sustainability policy literature include the requirements for support mechanisms and capacity building to empower individuals to contribute as innovators and entrepreneurs and not just consumers. The sustainable entrepreneurship framework can be applied by policymakers to develop context-specific policies: this is illustrated with a worked example of EU policy recommendations. The paper also outlines a method for crowdsourcing policy innovations

Policy for sustainable entrepreneurship: a crowdsourced framework

Sustainable entrepreneurship—entrepreneurship with social and ecological gains as well as economic ones—has the potential to play a significant role in addressing societal and environmental challenges. However, sustainability and entrepreneurship have hitherto been addressed through separate policy regimes, and it is not clear how policymakers can encourage sustainable entrepreneurship specifically. The authors develop a policy framework for sustainable entrepreneurship, using an open innovation approach with policymakers, business executives, academics, entrepreneurs and other relevant actors, including an online crowdsourcing event with 150 participants. The framework incorporates five policy domains: creating awareness and skills; building networks; funding and investing; measuring impact and performance; and innovating government. The article proposes a modified version of the multi-level perspective (MLP) on how socio-technical transitions occur, since the findings suggest that policy can catalyze the facilitation and aggregation of innovations coming from the niche level, thereby evolving the socio-technical regime, in addition to the role of policy described in earlier work in stabilizing the socio-technical regime. Contributions to entrepreneurship policy literature include the policy domain of measuring impact and performance, as appropriate success measures are non-trivial in a triple bottom line environment, and the potential for open policy innovation in entrepreneurship policy. Contributions to sustainability policy literature include the requirements for support mechanisms and capacity building to empower individuals to contribute as innovators and entrepreneurs and not just consumers. The sustainable entrepreneurship framework can be applied by policymakers to develop context-specific policies: this is illustrated with a worked example of EU policy recommendations. The paper also outlines a method for crowdsourcing policy innovations

Two-Qubit Gate Set Tomography with Fewer Circuits

Gate set tomography (GST) is a self-consistent and highly accurate method for the tomographic reconstruction of a quantum information processor's quantum logic operations, including gates, state preparations, and measurements. However, GST's experimental cost grows exponentially with qubit number. For characterizing even just two qubits, a standard GST experiment may have tens of thousands of circuits, making it prohibitively expensive for platforms. We show that, because GST experiments are massively overcomplete, many circuits can be discarded. This dramatically reduces GST's experimental cost while still maintaining GST's Heisenberg-like scaling in accuracy. We show how to exploit the structure of GST circuits to determine which ones are superfluous. We confirm the efficacy of the resulting experiment designs both through numerical simulations and via the Fisher information for said designs. We also explore the impact of these techniques on the prospects of three-qubit GST.Comment: 46 pages, 13 figures. V2: Minor edits to acknowledgment

Mode profiling of THz fibers with dynamic aperture near-field imaging

We present terahertz near-field mode profiling of different polymer THz fibers. Images with a resolution below the THz wavelength show the fundamental mode profile and higher order modes appearing at higher frequencies.2 page(s

Inference of α\alpha-particle density profiles from ITER collective Thomson scattering

The primary purpose of the collective Thomson scattering (CTS) diagnostic at ITER is to measure the properties of fast-ion populations, in particular those of fusion-born $\alpha$-particles. Based on the present design of the diagnostic, we compute and fit synthetic CTS spectra for the ITER baseline plasma scenario, including the effects of noise, refraction, multiple fast-ion populations, and uncertainties on nuisance parameters. As part of this, we developed a model for CTS that incorporates spatial effects of frequency-dependent refraction. While such effects will distort the measured ITER CTS spectra, we demonstrate that the true $\alpha$-particle densities can nevertheless be recovered to within ~10% from noisy synthetic spectra, using existing fitting methods that do not take these spatial effects into account. Under realistic operating conditions, we thus find the predicted performance of the ITER CTS system to be consistent with the ITER measurement requirements of a 20% accuracy on inferred $\alpha$-particle density profiles at 100 ms time resolution.Comment: 17 pages, 11 figures. Accepted for publication in Nucl. Fusio

Factors influencing the prevalence of resistance-associated substitutions in NS5A protein in treatment-naive patients with chronic hepatitis C

Direct-acting antivirals (DAAs) revolutionized treatment of hepatitis C virus (HCV) infection. Resistance-associated substitutions (RASs) present at the baseline impair response to DAA due to rapid selection of resistant HCV strains. NS5A is indispensable target of the current DAA treatment regimens. We evaluated prevalence of RASs in NS5A in DAA-naïve patients infected with HCV 1a (n = 19), 1b (n = 93), and 3a (n = 90) before systematic DAA application in the territory of the Russian Federation. Total proportion of strains carrying at least one RAS constituted 35.1% (71/202). In HCV 1a we detected only M28V (57.9%) attributed to a founder effect. Common RASs in HCV 1b were R30Q (7.5%), L31M (5.4%), P58S (4.4%), and Y93H (5.4%); in HCV 3a, A30S (31.0%), A30K (5.7%), S62L (8.9%), and Y93H (2.2%). Prevalence of RASs in NS5A of HCV 1b and 3a was similar to that worldwide, including countries practicing massive DAA application, i.e., it was not related to treatment. NS5A with and without RASs exhibited different co-variance networks, which could be attributed to the necessity to preserve viral fitness. Majority of RASs were localized in polymorphic regions subjected to immune pressure, with selected substitutions allowing immune escape. Altogether, this explains high prevalence of RAS in NS5A and low barrier for their appearance in DAA-inexperienced population.Fil: Kyuregyan, Karen K.. Russian Academy Of Sciences; Rusia. Russian Medical Academy Of Continuous Professional Education; Rusia. I. I. Mechnikov Research Institute For Vaccines And Sera; RusiaFil: Kichatova, Vera S.. Russian Medical Academy Of Continuous Professional Education; Rusia. Russian Academy Of Sciences; Rusia. I. I. Mechnikov Research Institute For Vaccines And Sera; RusiaFil: Karlsen, Anastasiya A.. I. I. Mechnikov Research Institute For Vaccines And Sera; Rusia. Russian Medical Academy Of Continuous Professional Education; Rusia. Russian Academy Of Sciences; RusiaFil: Isaeva, Olga V.. I. I. Mechnikov Research Institute For Vaccines And Sera; Rusia. Russian Medical Academy Of Continuous Professional Education; RusiaFil: Solonin, Sergei A.. N.V. Sklifosovsky Research Institute for Emergency Medicine; RusiaFil: Petkov, Stefan. Karolinska Huddinge Hospital. Karolinska Institutet; SueciaFil: Nielsen, Morten. Technical University of Denmark; Dinamarca. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; ArgentinaFil: Isaguliants, Maria G.. Russian Academy Of Sciences; Rusia. Karolinska Huddinge Hospital. Karolinska Institutet; SueciaFil: Mikhailov, Mikhail I.. Russian Medical Academy Of Continuous Professional Education; Rusia. I. I. Mechnikov Research Institute For Vaccines And Sera; Rusi

Anomalies and the chiral magnetic effect in the Sakai-Sugimoto model

In the chiral magnetic effect an imbalance in the number of left- and right-handed quarks gives rise to an electromagnetic current parallel to the magnetic field produced in noncentral heavy-ion collisions. The chiral imbalance may be induced by topologically nontrivial gluon configurations via the QCD axial anomaly, while the resulting electromagnetic current itself is a consequence of the QED anomaly. In the Sakai-Sugimoto model, which in a certain limit is dual to large-N_c QCD, we discuss the proper implementation of the QED axial anomaly, the (ambiguous) definition of chiral currents, and the calculation of the chiral magnetic effect. We show that this model correctly contains the so-called consistent anomaly, but requires the introduction of a (holographic) finite counterterm to yield the correct covariant anomaly. Introducing net chirality through an axial chemical potential, we find a nonvanishing vector current only before including this counterterm. This seems to imply the absence of the chiral magnetic effect in this model. On the other hand, for a conventional quark chemical potential and large magnetic field, which is of interest in the physics of compact stars, we obtain a nontrivial result for the axial current that is in agreement with previous calculations and known exact results for QCD.Comment: 35 pages, 4 figures, v2: added comments about frequency-dependent conductivity at the end of section 4; references added; version to appear in JHE

How do general practitioners experience providing care to refugees with mental health problems? A qualitative study from Denmark

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Relativistic quantum chemistry on quantum computers

Last years witnessed a remarkable interest in application of quantum computing for solving problems in quantum chemistry more efficiently than classical computers allow. Very recently, even first proof-of-principle experimental realizations have been reported. However, so far only the non-relativistic regime (i.e. Schroedinger equation) has been explored, while it is well known that relativistic effects can be very important in chemistry. In this letter we present the first quantum algorithm for relativistic computations of molecular energies. We show how to efficiently solve the eigenproblem of the Dirac-Coulomb Hamiltonian on a quantum computer and demonstrate the functionality of the proposed procedure by numerical simulations of computations of the spin-orbit splitting in the SbH molecule. Finally, we propose quantum circuits with 3 qubits and 9 or 10 CNOTs, which implement a proof-of-principle relativistic quantum chemical calculation for this molecule and might be suitable for an experimental realization